1. Field of the Invention
This invention relates to non-fried, oil-free, instant cooking dry noodle products. More particularly, the invention relates to dry precooked noodles which can be rehydrated and made ready to eat by immersing them in a hot liquid for a short period. This invention also relates to a method of manufacturing said noodles.
2. Description of the Prior Art
Conventional, i.e., non-instant, noodle products are well known in the art. Typically, such noodle products are prepared by mixing flour and other ingredients to form a dough. This dough is then formed into desired shape by rolling, cutting, pressing, extruding, and other techniques well known in the art. These shapes are subsequently dried for storage. This drying hardens the discrete particles of shaped noodle products.
Conventional noodle products must be cooked in very hot liquid for about 10 to 20 minutes to prepare them for eating. This cooking causes alpha-conversion of the starch in the product. Alpha-conversion, also known in the art as gelatinization, occurs when water penetrates the polymeric structure of the starch granule, thereby freeing and hydrating the polymers and causing the starch to swell. When swelling is sufficient so that crystallinity is no longer observable and the polymers are fully hydrated, gelatinization is complete. Conventional noodle manufacturing processes do an insignificant amount, if any, of alpha-conversion, so the cooking period must be long. However, prior art noodle products marketed as "instant cooking" have greater than about 85% alpha-conversion. Therefore, the process of preparing instant noodles requires less time.
Various methods known in the art reduce the time required to prepare noodle products by increasing the degree of alpha-conversion before sale to the consumer. For example, noodle products prepared conventionally can be precooked and then either pasteurized or frozen and packaged. Such precooked products need only be heated before being served. However, because these products have a high water content, the alpha-converted starches undergo beta-conversion during storage. Beta-conversion, which completely cleaves the starch molecule into two molecules, causes the product to taste as if it had not been thoroughly cooked and is obviously undesirable. Additional disadvantages are that the pasteurized product has a short useful life and the frozen product must be maintained and stored under freezing conditions.
The problems associated with producing alpha-converted noodles products are known in the art. For example, is it well known in the art that highly gelatinized noodle products tend to stick together. However, few of the methods developed to overcome this problem yield noodle products which consistently have pleasing organoleptic qualities and commercially practical shelf lives and can be easily prepared by the consumer.
One unsatisfactory prior art method coats noodle products with edible oils or fats; see U.S. Pat. No. 4,098,906. Other methods fry the noodle products in oil, as in U.S. Pats. Nos. 4,230,735 and 4,393,397. However, oil will always be present in these noodle products and will oxidize, thereby producing rancity and off odors.
Other methods of producing instant cooking noodle products have also been developed. For example, U.S. Pat. No. 4,234,617 discloses that use of hydrolyzate of a starch derived from the root, stem, or stalk of certain plants yields a product which quickly absorbs water. Therefore, noodle products containing these starches rehydrate quickly. U.S. Pat. No. 4,423,082 discloses a method for manufacturing instant cooking pasta products wherein saturated steam is introduced into the dough (a combination of water and dry cereal flour). This mixture is then kneaded and extruded to produce some alpha-conversion. In a second extrusion step, which develops the desired shape of the particles, the exterior of the extruder is jacketed to cool the product.
Still another method, the addition of leavening agents, is disclosed in U.S. Pat. No. 4,469,711. A carbonate and an acidic leavening salt are added to a dough mixture. The entire mixture is extruded to product conditions of pressure and temperature which permit the reaction of the carbonate with the acidic leavening salt to product CO.sub.2 within the body of the extruded noodle particle. This product is said to be a completely gelatinized product (the alphaconversion is 100%) which is slightly chewy upon reconstitution. The improvement disclosed in U.S. Pat. No. 4,495,214, wherein an "interrupter" is added to the dough made and processed in the fashion described in U.S. Pat. No. 4,469,711, is useful in improving the texture. Both techniques are coplex and yield a less satisfactory product.
Various other methods produce a porous structure within the noodle product particle. For example, U.S. Pat. No. 4,243,689 teaches a process wherein a dough web is steamed until the alpha-conversion is at least 93%, after which the web is predried, shaped, and finished dried. U.S. Pat. No. 4,370,352 requires an 85% alpha-conversion before the web is further processed and discloses that the resulting noodle product has a pore volume of 0.07 to 0.40 ml/g. U.S. Pat. No. 4,243,690 discloses a process wherein the dough is steamed until the alpha conversion is between 60 and 80%. The resulting product is shaped, and then steamed again until the desired alpha-conversion of 90% is attained. Another method requires that the porous structure be developed within the dough sheet before the desired shapes are cut therefrom so that the porous structure is exposed at the cut edges; see U.S. Pat. No. 4,208,439.
It is an object of this invention to provide non-fried, oil-free, instant cooking dry noodle products which can be prepared by immersing them in hot edible liquid for a short period, thereby yielding an organoleptically pleasing food product.
It is a further object of this invention to provide such products which have a very high pore volume.
Another object of this invention is to provide a method for manufacturing such noodle products.